The present disclosure relates to a decoding device and a decoding method, and a program, and more particularly relates to a decoding device and a decoding method by which decoding can be carried out more precisely, and a program for use therein.
In recent years, for example, a research in a communication field such as mobile communication, and a broadcasting field such as a terrestrial broadcasting or a satellite digital broadcasting has been remarkably advanced. Along with the advance of this research, with the view to increased efficiency of error-correction encoding and decoding, a research about the coding theory is actively being carried out.
A Shannon limitation given by a communication path encoding theorem made by C. E. Shannon is known as a theoretical limitation of encoding performance. A research about the encoding theory is carried out for the purpose of developing the code showing the performance close to the Shannon limitation. In recent years, Low Density Parity Check codes (hereinafter referred to as “LDPC codes”) as an encoding method known from the past are being in the limelight.
The LDPC coding was firstly proposed in a Non-patent Document 1 of R. G. Gallagar: “Low-Density Parity-Check Codes,” IRE Transactions on Information Theory, 1962. After that time, the LDPC encoding has arrived at re-attention in “D. J. C. Mackay: “Good error correcting codes based on very sparse matrices,” IEEE Trans. Inf. Theory, IT-45, pp. 399 to 431, 1999, “M. G. Luby, M. Mitzenmacher, M. A. Shokrollahi and D. A. Spielman: “Analysis of low density codes and improved designs using irregular graphs,” in Proceeings of ACM Symposium on Theory of Computing, pp. 249 to 258, 1998,” and the like.
With regard to the LDPC encoding, from the recent research, it is being found out that the performance close to the Shannon limitation is obtained as the code length is lengthened. Also, as described above, the LDPC coding is adopted in the terrestrial digital broadcasting standard. For example, the LDPC coding is adopted in DVB-T2 (Digital Video Broadcasting-Terrestrial 2), DVB-C2 (Digital Video Broadcasting-Cable 2), DTMB (Digital Terrestrial Multimedia Broadcast), and the like.